Light-emitting devices manufactured with compound semiconductor light-emitting diodes can realize various colors and are used for various applications including lamps, electric display boards, and displays. In particular, since the light-emitting device can realize white light, it is used for general lighting.
Generally, white light can be obtained by a combination of the blue light-emitting diode and phosphors. FIG. 1A shows the light-emitting diode 2 covered by the phosphor layer 1. The light-emitting diode 2 is connected to the substrate 58 by one or more conductive units 5. The material of the conductive unit can be metal such as Au, Cu, Sn, Ag, Al, or an alloy such as AuSn or AgSn, and the conductive unit 5 is generally formed by evaporation. Eutectic bonding process is a common method for connecting the light-emitting diode 2 and the substrate 58. Since the structure of the conductive unit formed by evaporation is loose, the conductive unit would shrink during the eutectic bonding process. FIG. 1B shows the light-emitting diode 2 is connected to the substrate 58 with the conductive units 5 which is shrunken. Since the shrinking effect of the conductive units 5 occurs, a portion of the phosphor layer 1A flows into the space between the substrate 58 and each of the conductive units 5 so a gap 100 is formed and causes the eutectic bonding to fail.